From owner-qrp-l@Lehigh.EDU Sun Mar 2 12:34:48 1997 Received: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id MAA19887 for ; Sun, 2 Mar 1997 12:34:47 -0500 (EST) X-Received-x: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id MAA19887 for ; Sun, 2 Mar 1997 12:34:47 -0500 (EST) Received: from Lehigh.EDU ([127.0.0.1]) by fidoii.cc.lehigh.edu with SMTP id <35757-42469>; Sun, 2 Mar 1997 12:33:42 -0500 Received: from nss2.CC.Lehigh.EDU ([128.180.1.26]) by fidoii.cc.lehigh.edu with ESMTP id <35748-18920>; Sun, 2 Mar 1997 12:32:21 -0500 Received: from SWBELL.net (mail1.rcsntx.swbell.net [151.164.1.2]) by nss2.CC.Lehigh.EDU (8.8.5/8.8.5) with ESMTP id MAA29269 for ; Sun, 2 Mar 1997 12:32:07 -0500 Received: from oj (ppp-207-193-8-79.hstntx.swbell.net [207.193.8.79]) by SWBELL.net (8.7.5/8.7.1) with SMTP id LAA12064 for ; Sun, 2 Mar 1997 11:32:04 -0600 (CST) Message-Id: <3319B936.557D@swbell.net> Date: Sun, 02 Mar 1997 11:30:30 -0600 Reply-To: k1oj@swbell.net Sender: owner-qrp-l@Lehigh.EDU Precedence: bulk From: "Owen 'OJ' Quarles" To: "Low Power Amateur Radio Discussion" Subject: FYBO ANTENNAS DE K1OJ MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Mailer: Mozilla 3.01C-SBXA (Win95; I) X-Listprocessor-Version: 8.1 beta -- ListProcessor(tm) by CREN Status: RO Howdy from Texas! Well FYBO has come and gone and I have almost recovered. I recieved some e-mail requests for info on the antennas I was using and thought I would share the following with all. In addition to the double size G5RV (204ft) that I used on 80m, I had a monoband 8JK on both 20m and 40m. Here is the scoop...... W8JK ARRAY: Feed is connected halfway between dipoles with twinlead or balun and coax. For optimum performance, the array should be erected horizontally a minimum of 1/2 wavelength above ground.When fed in the center, the array produces a bi-directional pattern. The array may be made directional by attaching the feed to one of the dipoles.The pattern will be directed towards the 'other' dipole. Connecting a string the length of 'B' between the ends of the dipoles will help keep the spaceing of the wires uniform. Computer modeling of these antennas at the 50 ft I had them erected at showed 6.3db gain on 40m and 9.6db on 20m. The idea to use these antennas came from a local ham, W5SB-Bill. He uses stacked versions of this antenna with great results. He frequently opens his shack to operators for many of the contests and his station never fails to perform well. Here is a rough diagram and the calculated measurements I used: _________________________ ________________________ A | | A | | | | <--450 ohm ladder line | | length 'B' | | | | \ / X <--- HALF TWIST (180 DEG ) / \ | | | | | | | | | | _________________________| |________________________ A A 20M A=29.4FT B=8.46FT 40m A=58.7FT B=16.9FT 80M A=134.9FT B=38.9FT 'B' Is an electrical 1/8 wavelength with a 1/2 twist between dipoles. I used random lengths of 450 ohm line to feed these antennas and had very good results with them. They are carefully rolled up and awaiting QTTF! CU---OJ---K1OJ HOUSTON,TX QRP-L #732 ..